Intrainfusion Drug Monitoring and Algorithm-Based Dose Adjustments for Children With ALL Receiving High-Dose Methotrexate Are Feasible and Safe in Costa Rica, a Low- and Middle-Income Country.

Purpose: Infusions of high-dose methotrexate at 5 g/m over 24 (HDMTX) as a single infusion for pediatric patients with high-risk precursor B-cell ALL are known to lead to superior outcomes. The Hospital Nacional de Niños Dr Carlos Sáenz Herrera, part of the public system Caja Costarricense de Seguro Social in Costa Rica (HNN), has been historically unable to provide this therapy secondary to the required intensive monitoring and cost-prohibitive toxicity support.

Methods: We report our experience providing HDMTX at HNN, to our knowledge, for the first time using an algorithm-based individualized HDMTX protocol designed to prevent toxic levels of methotrexate.